#include<iostream>
#include<string>
using namespace std;

class Base {
private:
	virtual void show() = 0;
public:
	void myShow() { show(); }
};

class Demo :public Base {
private:
	string name;
	void show() {
		cout << "demo show ==> TJ !\n";
	}
public:
	Demo(string name) : name(name) { cout << "name: " << name << endl; }
};

int main() {
	Demo de("123");
	de.myShow();
	
}